Severe acute respiratory syndrome and respiratory protection.
D006801:Humans; D017053:Infection Control / Q000379:methods; D017758:Infectious Disease Transmission, Patient-to-Professional / Q000517:prevention & control*; D012134:Respiratory Protective Devices; D045169:Severe Acute Respiratory Syndrome / Q000517:prevention & control* / Q000635:transmission; D014481:United States